The electron transport chain is the terminal step of aerobic respiration. It occurs on the inner membrane of the mitochondria. Reduced coenzymes NADH and FADH₂ are produced during glycolysis and Krebs cycle. When NADH and FADH₂ move along electron transport chains, high-energy electrons are released from NADH and FADH₂ produce ATP. The final electron acceptor in the process is free oxygen. Each NADH produces 3 ATP and each FADH₂ produces 2 ATP. Therefore, a total of 32 ATP molecules are generated in electron transport. Therefore, the electron transport system releases a lots of energy for cheetah to run fast.